I was routinely torquing the heads and adjusting the valves on my Dover white R60/2 on a Sunday. When I finished, I was reinstalling the left valve cover when the center stud pulled out. Some ham-fisted mechanic, either me or (I like to think) a previous owner tightened the acorn nut too much. |
I let Vech know my problem and he said I could fix it myself. Following his instructions, I went to an auto supply store and purchased a Heli-Coil 8mm x 1.25 pitch kit (photo left). Then I stopped at Sears to get the required 21/64-inch drill and a needed T-handle tap wrench. Returning home I viewed an instructional video on You Tube and proceded to install the Heli-Coil in the head.
That deed being done, I reinstalled the valve cover and reset the timing, which had not been set for a long time and was off. Thereafter I adjusted the idle jets. Using the EMPI carb synch gauges (photo in the next story below), I then balanced the throttle cables and the bike ran fine.
1955 R67/3 trouble shooting December 2009
The R67/3 is the rarest postwar BMW motorcycle. Only 700 were produced in 1955 and 1956, overlapping for one year the introduction of the Earles-fork and swing-arm equipped "slash-2" models. I was thrilled to be able to purchase one in December 2009 and had it shipped to me.
Part 1: carburetion
When I got this rare beauty home, I put gas in her and started her up. She would not idle and backfired when revved up. Then she would die and not restart. Damn! Consulting with experts like Vech and Tim Stafford, I began my work on Dec. 27. That day I retorqued the heads and set the valves. Installed new spark plugs.
Dec. 28: I talked with Vech and checked compression 100 PSI right, 105 left; good for an R67. I replaced the fuel hose without filters to be certain the fuel was flowing freely. I removed, diassembled the carburetors and cleaned them with carb cleaner.
Dec. 29: Removed carb tubes so I could use EMPI's carburetor sync gauges. Checked to make certain the magneto line lined up in the "V" on the front of the engine when the mark above the "S" was visible in the timing hole above the flywheel. I moved the magneto slightly counterclockwise to line up the "V". Checked timing static and it seemed o.k. Bike started with two kicks and died in about 10 seconds. Would not restart, even rolling down an incline and releasing the clutch in second gear.
EMPI carb sync gauge on the right side carburetor (engine off)
Dec. 30: Today I pressed down on the float buttons for 4 seconds in case the bike was not getting enough fuel. The bike started on the second kick and kept running if I occasionally pressed the buttons! Timing was o.k. with mark above "S" staying in the window at idle so long as I kept the engine running. More phone conversations with Vech, who proved to be incredibly patient with me. He felt the throttle slides might be bottoming out. He told me how to address this and referred me also to his tech pages, especially this one.
Dec. 31: Today I adjusted the throttle slides and cables according to Vech’s instructions and then adjusted the idle air mix screws. Bike started on one kick. I then adjusted the carb synch cables using the EMPI gauges so they were equalized through the rev range. Bike runs beautifully!
Part 2: the front brake
Above left: /2 cable retainer on the left, /3 retainer in the middle. Note the outside diameter and hole in the /3 retainer are much smaller. The retainer on the right was made by Vech to fit a /2 brake arm and a /3 brake cable, and it solved the problem. Above right: The retainer hole in the brake arm had been drilled out to take the /2 retainer, but the /3 cable end is too small to fit the /2 retainer correctly.
When I first rode the bike, it had no front brake. Upon further investigation, It appeared that while the brake cable was fine, there was a problem with the lower cable retainer in the lower brake arm. The hole in the retainer was too large to stop the end of the cable from slipping through it. I obtained a correct retainer from Vech, but it was too small for the hole in the brake arm. Another discussion with Vech, and comparison with the brake on my R51/3 showed that while the brake arm on the R67/3 is correct for this bike, it had been drilled out to hold the larger /2 retainer, which does not fit the /3 brake cable correctly.
The solution? A new brake arm, which Vech said would take about three weeks to obtain from Germany. Vech scratched his head and said he thought he could make a one-of-a-kind retainer for a /3 brake cable with a larger outside diameter to fit the /2 hole that had been drilled in my /3 arm. About two hours later he called and said he had done just that in stainless steel, and it is shown on the right in the left photo above. It solved the problem by allowing me to install the /3 cable into an oversized hole that was drilled to hold a /2 retainer.
Part 3: the headlight
The headlight on the R67/3 had been replaced with a nonstandard H4 reflector and bulb. That is fine, except it is not original to the bike. Being a fussy sort, I decided I needed to replace that with a stock reflector, stock socket, and stock incandescent bulb. Vech to the rescue, he sent the needed parts.
Jan. 16, 2010: follow-up
|A couple of minor items should finish the bike, which runs beautifully now and demonstrates a significant power increase over an R51/3. Vech has had made new Albert rear view mirrors that clamp on the handlebars (photo left), and I have installed a pair. |
The speedometer that came on the bike was a 1.2 ratio MPH speedo for an R50/2 or R60/2 and reads much faster than the speed I am riding. For MPH, it should be a 1.52 ratio, and these are not available. So I replaced it with a new 0.95-ratio kilometers speedometer from Vech (photo right), which is correct for the 35/9 rear drive on the bike. With these changes, the bike is finished and is a complete joy to ride.
1967 R60/2 exhaust valve December 2009
In late November I was riding my black 1967 R60/2 north on the Pinal Parkway to attend the vintage bike show at Victory BMW in Chandler. Jim Strang was accompanying me, riding my red 1967 R60/2. I was traveling at 60 MPH about halfway between Oracle Junction and Florence when the engine on my bike started making metallic clattering noises and the engine stopped. It had only 290 miles on a top end job. Damn. It would not restart. Perhaps I had been pushing it too hard?
I parked the disabled BMW off the roadway as Jim and I pondered what to do next. After a while I tried to start it again. It started! We turned around and headed back toward Tucson, going no faster than 45 MPH. Amazingly, the old Beemer did not miss a beat. We got home without incident, except, perhaps, for a few frustrated drivers behind us who felt we were going too slowly.
O.K. The bike was home but I could not ride it further without fixing whatever was wrong. I checked the compression and found it read only 70 PSI on the right side. It should read 100-110 PSI on an R60/2. Something was definitely wrong on the right.
I removed the valve cover, something I had done often in the past. Then I removed the rocker arms and push rods and pulled the head, something I had done once or twice. Peering into the cylinder with the piston bottom dead center and examining the valves, my inexpert eyes could detect nothing wrong. Then I removed the cylinder and piston — totally new tasks to me — and headed to Iron Horse, to show everything to Matthew Noli. I knew that Iron Horse would not work on the bike, but I also knew that Matthew was very knowledgeable about /2s. (Incidentally, standard procedure to remove the wrist pin from the cylinder and connecting rod is to warm the cylinder with a torch. Not having one, I tried my Sears industrial heat gun, and it worked just fine in lieu of a torch with no flame.)
Matthew gave me his assessment. He noticed a nick on the top of the piston that was caused by the exhaust valve.
“Bent exhaust valve,” opined Matthew.
For some reason the valve did not retreat fast enough into the head and the piston had bumped it back up onto its seat. I was not over-revving the engine, so something else must have caused that.
Crap, thought I. Now what? Well, at least I had got the piston, cylinder, and head off. Matthew recommended I take the head to Machine Works, on Elm Street, which I promptly did.
At Machine Works, I made the acquaintance of John O’Hara, who was advertised as “The best head man in Tucson.” He removed the exhaust valve and put it into what looked like half of a lathe. He spun it around.
“Yup,” said John, “See that? The valve is bent.”
I didn’t have a spare exhaust valve in my pocket, and you cannot get a /2 exhaust valve at Sears, so I had Tim Stafford in San Diego send me a new one.
The valve arrived. Back I went to Machine Works where Big John, the head man — who is a very nice guy — did his magic on the valve seat and guide and installed the new valve.
All that was fine, but then I had to install the piston, cylinder, and head, torque the head bolts, set the valves, and put the valve cover back on. Somewhat nervously, and following Betjemann’s book, I accomplished those tasks. I then ran the engine, let it cool overnight and reset the head bolts and valves in the morning.
I have since ridden Iowa for many miles and at high speeds without further problems.
In December 2010, I was frustrated by the fact that Iowa would not idle at the same engine speed when hot and cold. It would idle roughly when the engine was warm, but fine when cold. In checking around I felt air puffing out of the left exhaust nut when the engine was running. I tightened the nut, but the puffing continued. Then I removed the nut, and found that the crush washer under it was completely flattened. I installed a new washer and the puffing stopped and the idle ran the same hot or cold. A simple solution that was effective.
I also noticed that when riding much faster than 65 MPH, I would feel a small front end wobble which would worsen with greater speed. I checked the tapered steering head bearings and found them to be too loose. I then tightened them.
1968 R60US front forks December 2009
My next project involved another problem with the Dover white 1968 R60US.
The US models have telescopic forks instead of the more common Earles forks found on /2s. I have to ride about ¼ mile from my house on a dirt road until I get to pavement. The R60US forks made banging noises every time I did that, indicating something was wrong up front. I wanted that to be fixed.
I emailed Vech and told him the symptoms.
“Hell, I know what that is already,” he wrote back. Where upon he listed for me all the parts I would need to fix the forks.
Of course, that meant that someone would have to disassemble the forks to install all the new parts Vech was sending me. I took a deep breath and reached again for Betjemann’s book. Who else was going to do it?
I love what Betjemann says about working on US forks. A direct quote from page 95:
“Servicing these forks is relatively easy….”
When I see the word “easy” associated with any task, it is a major warning. I learned that again in October when I decided to replace the faucet on our kitchen sink. In those instructions, the word “easy” appeared twice in the first sentence — an even more ominous warning! Well, I will not print here the words I uttered while replacing the faucet, but “easy” was not one of them.
The front forks came completely apart. The parts arrived from Vech. I read and re-read the part of Betjemann’s book on the “easy” repair of the forks. I prayed for more photographs to guide me in the reassembly process, but none appeared. Reading and rereading the text and making sure I understood the terms for the parts being assembled took a lot of time that could have been saved had more illustrations been provided.
Proceeding cautiously and anxiously, It took me two days to get the forks back together with the new parts. Two whole days!
Near the end of the first day I was so exhausted my addled brain ceased functioning, and I stopped work in order to save the motorcycle and myself from potential injury.
I finally finished the repairs to the best of my ability. On the third day I took the R60US off the lift and then rode it up and down my dirt road. It was better, but not as quiet as the nearly identical forks on my R75/5. I guess I have more to learn about perfecting US forks.
No doubt something else will crop up, and I will face again the challenge to keep another old BMW running.
1968 R60US transmission March 2009
The first time I bit the bullet was last winter when I found that the transmission on my Dover white 1968 R60US did not like to stay in first gear going up a very steep hill near our house. What to do? There was no way I could open up the interior of a tranny and work on it. I called Craig “Vech” Vechorik in Mississippi, a very well known vintage-BMW parts supplier and wrench, and asked him what to do.
“Send me the transmission,” said he.
“I’ll tell you what to do!”
And he did, over the course of several phone calls. I placed the bike on my Harbor Freight motorcycle lift and applied his instructions. I amazed myself by actually removing the transmission from the bike. I sent it to Vech. A couple of weeks later, back it came. More phone calls. Eventually I got transmission got back in its proper place. Incredibly, it actually worked!
Left photo: an R60/2 on Harbor Freight's motorcycle lift.
Fifty-five years of BMW motorcycles:
R51/3   R67/3   R68   R60/2   Red R60/2   R69S   R75/5   R1200RT